CN114190881A

CN114190881A - Ophthalmic device

Info

Publication number: CN114190881A
Application number: CN202111026710.8A
Authority: CN
Inventors: 冈本圭一郎
Original assignee: Tomy Co Ltd
Current assignee: Tomy Co Ltd
Priority date: 2020-09-02
Filing date: 2021-09-02
Publication date: 2022-03-18
Also published as: JP2022042387A; US20220061658A1; EP3964119A1

Abstract

The invention provides an ophthalmologic apparatus. An ophthalmic device is provided with: a 1 st light source (26) that outputs a 1 st light beam; a 2 nd light source (76) that outputs a 2 nd light beam; a scanner (32) for scanning within a 1 st range of the eye to be examined using the 1 st light beam output from the 1 st light source and scanning within a 2 nd range of the eye to be examined different from the 1 st range using the 2 nd light beam output from the 2 nd light source; a 1 st objective lens (42) which is arranged between the scanner and the eye to be inspected and is used for irradiating a 1 st light beam used for scanning by the scanner to a 1 st range of the eye to be inspected; and a 2 nd objective lens (54) disposed between the scanner and the eye to be inspected, for irradiating a 2 nd light beam used for scanning by the scanner to a 2 nd range of the eye to be inspected. This can suppress noise from being mixed into the tomographic information.

Description

Ophthalmic device

Technical Field

The technology disclosed in this specification relates to an ophthalmologic apparatus. More specifically, the present invention relates to an ophthalmologic apparatus capable of acquiring tomographic information for different measurement ranges (for example, anterior segment (anterior segment), fundus oculi, and the like) of an eye to be examined.

Background

An ophthalmologic apparatus has been developed that acquires tomographic information for different measurement ranges of an eye to be examined. For example, the ophthalmologic apparatus of patent document 1 can acquire a tomographic image of an anterior ocular segment of an eye to be inspected and a tomographic image of a fundus of the eye to be inspected. The ophthalmic device has a light source for anterior segment and a light source for fundus oculi, wherein the wavelength of the light source for fundus oculi is different from that of the light source for anterior segment. Light from the anterior ocular segment light source is irradiated to the anterior ocular segment of the eye to be examined through an anterior ocular segment optical path in which a scanner and an objective lens are arranged. Light from the fundus oculi light source is branched by the scanner from the anterior segment optical path to the fundus oculi optical path in which the relay lens is disposed, and is merged again from the fundus oculi optical path to the anterior segment optical path, and is irradiated to the fundus oculi of the eye to be examined via the same objective lens. That is, a part of the optical path for the fundus oculi is the same as the optical path for the anterior segment. In this ophthalmologic apparatus, both the anterior segment tomographic image and the fundus tomographic image are acquired by sharing the scanner and the objective lens with the anterior segment and the fundus optical path branched or merged from or into the anterior segment optical path between the scanner and the objective lens.

In addition, the ophthalmologic apparatus of patent document 2 can also acquire a tomographic image of the anterior segment of the eye to be examined and a tomographic image of the fundus of the eye to be examined. In this ophthalmic apparatus, light from the anterior ocular segment light source is irradiated to the anterior ocular segment of the eye to be examined through the anterior ocular segment scanner and the objective lens. Light from the fundus light source passes through the fundus scanner and the relay lens, and is irradiated to the fundus of the eye through the same objective lens. That is, the ophthalmologic apparatus of patent document 2 includes an anterior segment scanner and a fundus scanner, respectively, and acquires both an anterior segment tomographic image and a fundus tomographic image by sharing an objective lens.

Documents of the prior art

Patent document

Patent document 1: U.S. patent grant publication No. 9072460

Patent document 2: japanese patent publication No. 2018-525036

Disclosure of Invention

[ problem to be solved by the invention ]

In the above-described conventional ophthalmologic apparatus, light from a plurality of light sources is irradiated to different measurement ranges of the eye to be examined in order to acquire tomographic information for the respective measurement ranges of the eye to be examined. Therefore, the configuration for acquiring the tomographic information for one measurement range has an influence on acquisition of the tomographic information for another measurement range, and there is a problem that noise is mixed in the acquired tomographic information. The present specification provides a technique for suppressing noise from being mixed into tomographic information in an ophthalmologic apparatus capable of acquiring tomographic information for different measurement ranges of an eye to be examined. [ solution for solving problems ]

The 1 st ophthalmic device disclosed herein has a 1 st light source, a 2 nd light source, a 1 st scanning optical system, a 2 nd scanning optical system, a 1 st interferometer, and a 2 nd interferometer, wherein the 1 st light source outputs a 1 st light beam; the 2 nd light source outputs a 2 nd light beam; the 1 st scanning optical system scans a 1 st range of the eye to be examined using a 1 st light beam output from a 1 st light source; the 2 nd scanning optical system scans a 2 nd range of the eye to be examined, which is different from the 1 st range, using a 2 nd light beam output from the 2 nd light source; the 1 st interferometer acquires 1 st range of tomographic information from 1 st interference light, wherein the 1 st interference light refers to interference light obtained from reflected light of the 1 st beam from the eye to be examined; the 2 nd interferometer acquires 2 nd range tomographic information from 2 nd interference light, wherein the 2 nd interference light refers to interference light obtained from reflected light of the 2 nd beam from the eye to be examined. The center wavelength of the 1 st beam is different from the center wavelength of the 2 nd beam. The 1 st scanning optical system has a 1 st objective lens section for irradiating a 1 st light beam to a 1 st area of an eye to be examined. The 2 nd scanning optical system has a 2 nd objective lens section for irradiating the 2 nd beam to the 2 nd field of the eye to be examined. The 1 st beam does not pass through the 2 nd objective lens part but passes through the 1 st objective lens part. The 2 nd beam does not pass through the 1 st objective lens part but passes through the 2 nd objective lens part.

In the above-described ophthalmologic apparatus, a 1 st objective lens unit dedicated for acquiring the 1 st range of tomographic information is disposed, and a 2 nd objective lens unit dedicated for acquiring the 2 nd range of tomographic information is disposed. Accordingly, compared with the related art ophthalmologic apparatus, it is possible to suppress noise from mixing into tomographic information.

That is, in the conventional ophthalmologic apparatus, the anterior segment measurement and the fundus portion measurement share the objective lens, and both the light of the anterior segment light source and the light of the fundus light source are irradiated to the eye to be examined through the same objective lens. With this configuration, light from the fundus oculi light source is irradiated to the fundus oculi of the eye through the 2 lenses of the relay lens and the objective lens. Therefore, the lens power (refractive power) required for optical scanning of the fundus is shared by 2 lenses. Therefore, the principal ray of light between the relay lens and the objective lens is always nearly parallel to the optical axis regardless of the scanning angle, and enters the objective lens disposed in the eye to be examined at an angle close to the perpendicular. As a result, there is a problem that noise generated by light reflected by the surface of the objective lens is captured in the tomographic image for the fundus oculi.

In the above-described ophthalmologic apparatus, there are provided a 1 st objective lens section dedicated for acquiring the 1 st range of tomographic information and a 2 nd objective lens section dedicated for acquiring the 2 nd range of tomographic information. Therefore, the 1 st objective lens unit can provide the 1 st range with the lens power for irradiating the 1 st range with light, and the 2 nd objective lens unit can provide the 2 nd range with the lens power for irradiating the 2 nd range with light. Therefore, the incident angle of light incident on the 1 st objective lens portion can be set relatively freely, and the incident angle of light incident on the 2 nd objective lens portion can be set relatively freely. Accordingly, it is possible to suppress noise generated by light reflected by the surface of the objective lens portion from being mixed into tomographic information.

The "objective lens unit" may be constituted by 1 lens (single lens), or may be constituted by a combination of a plurality of lenses housed in the same barrel. When the objective lens portion is formed by a combination of a plurality of lenses, it is preferable that the objective lens portion is formed by a bonded lens having the smallest number of interfaces with air, such as a doublet lens or a triplet lens.

The 2 nd ophthalmic device disclosed herein has a 1 st light source, a 2 nd light source, a 1 st scanning optical system, a 2 nd scanning optical system, a 1 st interferometer and a 2 nd interferometer, wherein the 1 st light source outputs a 1 st light beam; the 2 nd light source outputs a 2 nd light beam; the 1 st scanning optical system scans a 1 st range of the eye to be examined using a 1 st light beam output from a 1 st light source; the 2 nd scanning optical system scans a 2 nd range of the eye to be examined, which is different from the 1 st range, using a 2 nd light beam output from the 2 nd light source; the 1 st interferometer acquires 1 st range of tomographic information from 1 st interference light, wherein the 1 st interference light refers to interference light obtained from reflected light of the 1 st beam from the eye to be examined; the 2 nd interferometer acquires 2 nd range tomographic information from 2 nd interference light, wherein the 2 nd interference light refers to interference light obtained from reflected light of the 2 nd beam from the eye to be examined. Range 1 is the anterior segment of the eye under examination. The 2 nd range is a fundus portion of the eye to be examined. The center wavelength of the 1 st beam is different from the center wavelength of the 2 nd beam. The 1 st optical path has an overlapping section overlapping with the 2 nd optical path and a 1 st non-overlapping section not overlapping with the 2 nd optical path, wherein the 1 st optical path is an optical path of the 1 st light beam, and the 2 nd optical path is an optical path of the 2 nd light beam. The 2 nd optical path has the overlapping section and a 2 nd non-overlapping section that does not overlap with the 1 st optical path. The ophthalmic apparatus also has a target portion that faces the eye to be examined. The overlap section has a 1 st overlap section, and the 1 st overlap section includes a section connecting the subject's eye and the target portion. The ophthalmologic apparatus further has a 1 st dichroic mirror, and the 1 st dichroic mirror is disposed at a 1 st position, wherein the 1 st position is a position branching from the 1 st overlapping section to the 1 st non-overlapping section and the 2 nd non-overlapping section. The 1 st dichroic mirror reflects the 1 st light beam and transmits the 2 nd light beam. An AR Coating (Anti Reflection Coating) is applied to the back surface of the 1 st dichroic mirror for the wavelength band of the 1 st beam.

In the above-described ophthalmologic apparatus, the 1 st light beam output from the 1 st light source for anterior segment is reflected by the 1 st dichroic mirror, passes through the target portion, and is irradiated to the anterior segment of the eye to be examined. Accordingly, ghost noise generated by irradiating the anterior segment with light transmitted through a dichroic mirror (dichroic mirror) can be avoided. That is, when the anterior segment of the eye is irradiated with the light transmitted by the 1 st dichroic mirror, the back reflected light of the 1 st dichroic mirror is also irradiated with the anterior segment of the eye. Since the reflection intensity of the iris against light is strong, the back reflection light of the 1 st dichroic mirror is also strongly reflected by the iris, and accordingly, ghost noise is mixed into tomographic information. In the above-described ophthalmologic apparatus, when tomographic information of an anterior segment of an eye to be examined is acquired, the 1 st light beam reflected by the 1 st dichroic mirror is irradiated to the anterior segment of the eye to be examined, and therefore, ghost noise can be suppressed from being mixed into the tomographic information.

In the above-described ophthalmologic apparatus, an AR coating is applied to the back surface of the 1 st dichroic mirror for the wavelength band of the 1 st light beam. Accordingly, when acquiring the tomographic information of the anterior segment of the eye to be examined, the intensity of the reflected light of the 1 st light beam reflected by the back surface of the 1 st dichroic mirror can be suppressed, and the mixing of noise into the tomographic information can also be suppressed.

Drawings

Fig. 1 is a schematic configuration diagram of an optical system of an ophthalmic apparatus according to embodiment 1.

Fig. 2 is a diagram for explaining an anterior ocular segment scanning optical system of the ophthalmic apparatus of example 1.

Fig. 3 is a diagram for explaining a fundus scanning optical system of the ophthalmic apparatus of embodiment 1.

Fig. 4 is a diagram for explaining the configuration of a light receiving system for receiving light reflected from an eye to be inspected in the total refractive power measurement optical system of the ophthalmic apparatus of embodiment 1.

Fig. 5 is a diagram for explaining a front monitor optical system of the ophthalmic apparatus of embodiment 1.

Fig. 6 is a diagram for explaining a position detection and light projection system of the ophthalmic apparatus according to embodiment 1.

Fig. 7 is a diagram for explaining a position detection light receiving optical system of the ophthalmologic apparatus of example 1.

Fig. 8 is a diagram for explaining a fixation target optical system of the ophthalmic apparatus of embodiment 1.

Fig. 9 shows an example of a tomographic image in which reflection noise of an objective lens is captured in an ophthalmologic apparatus according to the related art.

Fig. 10 shows an example of an image captured with reflection noise of an objective lens when total refractive power measurement is performed in the ophthalmologic apparatus according to the related art.

Fig. 11 is a diagram for explaining the back reflection of the dichroic mirror.

Fig. 12 is an example of an anterior segment tomographic image of the eye E in which ghost noise generated by the back reflection of the dichroic mirror is captured.

Fig. 13 is a diagram for explaining the back reflection of light transmitted through the front surface of the dichroic mirror.

Fig. 14 is an example of an anterior segment tomographic image acquired when the iris signal intensity is changed.

Description of the reference numerals

26: a light source for anterior segment; 32: a two-dimensional scanner; 34. 40, 44, 56: a dichroic mirror; 42. 54: an objective lens; 76: a light source for the fundus oculi.

Detailed Description

In the ophthalmic apparatus disclosed in the present specification, the 1 st optical path may have an overlapping section overlapping with the 2 nd optical path and a 1 st non-overlapping section not overlapping with the 2 nd optical path, wherein the 1 st optical path refers to an optical path of the 1 st light beam, and the 2 nd optical path refers to an optical path of the 2 nd light beam. The 2 nd optical path may also have the overlapping section and a 2 nd non-overlapping section that does not overlap with the 1 st optical path. The 1 st objective lens portion may be disposed in the 1 st non-overlapping section. The 2 nd objective lens portion may be disposed in the 2 nd non-overlapping section. According to this configuration, the 1 st beam can be irradiated to the eye through the 1 st objective lens portion, and the 2 nd beam can be irradiated to the eye through the 2 nd objective lens portion.

In the ophthalmic apparatus disclosed in the present specification, the 1 st scanning optical system may further have a 1 st scanner that performs scanning using the 1 st light beam output from the 1 st light source. The 2 nd scanning optical system may also have a 2 nd scanner that performs scanning using the 2 nd light beam output from the 2 nd light source. The 1 st scanner may be disposed in the 1 st non-overlapping section, and the 2 nd scanner may be disposed in the 2 nd non-overlapping section. According to this configuration, the 1 st scanner can be applied to the 1 st range and the 2 nd scanner can be applied to the 2 nd range.

In the ophthalmologic apparatus disclosed in the present specification, it is also possible to have a scanner that performs scanning using the 1 st light beam output from the 1 st light source and performs scanning using the 2 nd light beam output from the 2 nd light source. The scanner may be disposed in the overlap section and shared by the 1 st scanning optical system and the 2 nd scanning optical system. The 1 st objective lens portion may also be disposed between the scanner and the eye to be examined. The 2 nd objective lens part may also be disposed between the scanner and the eye to be examined. According to this configuration, since the scanner is shared by the 1 st scanning optical system and the 2 nd scanning optical system, the number of parts of the optical system can be reduced. In addition, the scanner can be shared, and the device can be miniaturized.

In the ophthalmic device disclosed in the present specification, the 1 st range may be an anterior segment of the eye to be examined. The 2 nd range may be a fundus portion of the eye to be examined. The ophthalmic apparatus may also have a target portion that faces the eye to be examined. The overlap section may also have a 1 st overlap section, the 1 st overlap section including a section connecting the subject eye and the target portion. The ophthalmologic apparatus may further have a 1 st dichroic mirror, and the 1 st dichroic mirror may be disposed at a 1 st position, the 1 st position being a position branching from the 1 st overlapping section to the 1 st non-overlapping section and the 2 nd non-overlapping section. The 1 st dichroic mirror may reflect the 1 st beam and transmit the 2 nd beam. According to this configuration, when acquiring tomographic information of the anterior segment of the eye to be examined, the 1 st light beam reflected by the 1 st dichroic mirror is irradiated to the anterior segment of the eye to be examined. Therefore, ghost noise generated by irradiating the anterior segment with light transmitted through the dichroic mirror can be avoided.

In the ophthalmic apparatus disclosed in the present specification, an AR Coating (Anti Reflection Coating) may be applied to the back surface of the 1 st dichroic mirror for the wavelength band of the 1 st light beam. According to this configuration, when acquiring the tomographic information of the anterior segment of the eye to be inspected, the intensity of the reflected light of the 1 st light beam reflected by the back surface of the 1 st dichroic mirror is suppressed, whereby it is possible to further suppress noise from mixing into the tomographic information.

In the ophthalmic apparatus disclosed in the present specification, the overlap section may have a 2 nd overlap section including a section connecting the 2 nd position and the scanner, wherein the 2 nd position refers to a position where the 1 st non-overlap section and the 2 nd non-overlap section join or branch. The ophthalmic device may also have a 2 nd dichroic mirror, the 2 nd dichroic mirror being disposed at the 2 nd position. The 2 nd dichroic mirror may reflect the 1 st beam and transmit the 2 nd beam. According to this configuration, when acquiring tomographic information of the anterior segment of the eye to be examined, the 1 st light beam reflected by the 2 nd dichroic mirror is irradiated to the anterior segment of the eye to be examined. Therefore, ghost noise generated by irradiating the anterior segment with light transmitted through the dichroic mirror can be avoided.

In the ophthalmic apparatus disclosed in the present specification, an AR Coating (Anti Reflection Coating) may be applied to the back surface of the 2 nd dichroic mirror for the wavelength band of the 1 st light beam. According to this configuration, when acquiring the tomographic information of the anterior segment of the eye to be examined, the intensity of the reflected light of the 1 st light beam reflected by the back surface of the 2 nd dichroic mirror can be suppressed, thereby enabling suppression of noise from mixing into the tomographic information.

In the ophthalmologic apparatus disclosed in the present specification, the 3 rd dichroic mirror may be further disposed at a 3 rd position different from the 2 nd position among positions at both ends of the 2 nd overlapping section. The 3 rd dichroic mirror may reflect the 1 st beam and transmit the 2 nd beam. An AR Coating (Anti Reflection Coating) may be applied to the back surface of the 3 rd dichroic mirror for the 1 st wavelength band. According to this configuration, when acquiring the tomographic information of the anterior segment of the eye to be examined, the intensity of the reflected light of the 1 st light beam reflected by the back surface of the 3 rd dichroic mirror can be suppressed, thereby enabling suppression of noise from mixing into the tomographic information.

[ examples ]

Next, the ophthalmologic apparatus according to the present embodiment will be explained. The ophthalmologic apparatus according to the present embodiment can perform acquisition of a tomographic image of the anterior segment of the eye E, acquisition of a tomographic image of the fundus portion of the eye E, measurement of the total refractive power of the eye E, and the like. Therefore, information for comprehensively diagnosing the state of the eye E can be acquired by 1 ophthalmologic apparatus. In order to exert the above-described various functions, the ophthalmologic apparatus of the present embodiment has an optical system 10 shown in fig. 1. That is, the optical system 10 has an anterior ocular segment scanning optical system, a fundus scanning optical system, a total refractive power measuring optical system, a pre-monitor optical system, a position detection light projecting optical system, a position detection light receiving optical system, and a fixation target optical system. Next, each optical system will be explained.

As shown in fig. 2, the anterior ocular segment scanning optical system is composed of an anterior ocular segment light source 26 (an example of the 1 st light source), a collimator mirror 28, a dichroic mirror 30, a two-dimensional scanner 32, a dichroic mirror 34, a total reflection mirror 40, an objective lens 42 (an example of the 1 st objective lens part), and a dichroic mirror 44.

The anterior ocular segment light source 26 is a wavelength-scanning light source, and the wavelength (wave number) of the output light changes at a predetermined cycle. The anterior segment light source 26 can output light having a long wavelength, for example, light having a center wavelength of 0.95 μm or more and 1.80 μm or less. In the present embodiment, the anterior ocular segment light source 26 outputs light having a center wavelength of 1.31 μm. When light having a long wavelength is used, for example, opacity of the lens, a strong scattering tissue such as the ciliary body, the conjunctiva, and the sclera is easily transmitted, and the light is absorbed by water to a large extent and hardly reaches the fundus, so that strong light can be irradiated. Therefore, by outputting light having a center wavelength of 0.95 μm or more from the anterior segment light source 26, the reaching degree of the tissue made of the scattering material can be improved. Further, since the dispersion of light having a central wavelength of 0.95 μm or more and 1.80 μm or less due to water is small, when light in this range is irradiated to the eye E, an anterior segment OCT image having a good image quality can be obtained. Further, by outputting light having a center wavelength of 1.80 μm or less from the anterior ocular segment light source 12, the target site can be measured with high sensitivity by an indium gallium arsenide (InGaAs) based light receiving element. In the present embodiment, by outputting light of 0.95 μm or more and 1.80 μm or less from the anterior segment light source 26, a tomographic image of the anterior segment of the eye E can be appropriately captured.

Light (an example of the 1 st beam) output from the anterior segment light source 26 is emitted from an optical fiber (not shown) via the interferometer 25 and enters the collimator lens 28. The collimator lens 28 converts the light output from the anterior ocular segment light source 26 into parallel light. The light converted into parallel light by the collimator mirror 28 is reflected by the dichroic mirror 30 and enters the two-dimensional scanner 32. The two-dimensional scanner 32 scans the anterior segment of the eye E in 2 directions of the x direction and the y direction using the incident light. In the present embodiment, the two-dimensional scanner 32 uses a current scanner. In addition, the two-dimensional scanner 32 may use a scanner other than the current scanner, and may use, for example, a MEMS mirror capable of 2-axis scanning. The light emitted from the two-dimensional scanner 32 enters the objective lens 42 via the dichroic mirror 34 and the total reflection mirror 40. The light incident on the objective lens 42 passes through the objective lens 42, is reflected by the dichroic mirror 44, is condensed near the anterior segment of the eye E, and is irradiated on the eye E. In the present embodiment, the two-dimensional scanner 32 is disposed at the back focus of the objective lens 42. Therefore, the light emitted from the two-dimensional scanner 32 reaches the eye E in parallel with the optical axis (optical path L12). That is, in the present embodiment, the anterior segment of the eye E is scanned by telecentric scanning using a light beam. Further, a target portion 45 is disposed between the dichroic mirror 44 and the eye E. The target portion 45 is arranged at a position facing the eye E during measurement. The target portion 45 is provided in a not-shown housing, and the optical system 10 is housed in the housing.

The light reflected by the anterior segment of the eye E travels the same path as the above-described path, and is guided to the interferometer 25 (example of the 1 st interferometer) via an optical fiber (not shown). The interferometer 25 combines light reflected by the anterior segment of the eye E and reference light separately generated using light output from the anterior segment light source 26, detects interference light obtained by the combined light, and outputs an interference signal. In the ophthalmologic apparatus of the present embodiment, a tomographic image of the anterior segment of the eye E to be examined is acquired by processing the interference signal output from the interferometer 25.

As is apparent from the above description, in the anterior ocular segment scanning optical system, the optical path L3, a part of the optical path L4 (specifically, the range between the dichroic mirror 30 and the two-dimensional scanner 32), the optical path L5, the optical path L6, the optical path L8 (that is, the range between the total reflection mirror 40 and the dichroic mirror 44), and the optical path L12 are paths through which light passes.

As shown in fig. 3, the fundus scanning optical system is constituted by a fundus light source 76 (an example of the 2 nd light source), a lens 22, a polarization beam splitter 24, a dichroic mirror 30, a two-dimensional scanner 32, a dichroic mirror 34, a dichroic mirror 56, an objective lens 54 (an example of the 2 nd objective lens unit), and a dichroic mirror 44.

The fundus oculi light source 76 is a wavelength-fixed light source. The fundus light source 76 can output light having a center wavelength different from that of the light output from the anterior segment light source 26, for example, light having a center wavelength of 0.40 μm or more and 1.15 μm or less. For example, the fundus oculi light source 76 may output light having a half width in a wavelength range different from a half width (half width) wavelength range of the light output from the anterior segment light source 12. In the present embodiment, the light source 76 for fundus outputs light with a central wavelength of 0.83 μm. The transmittance of light having a central wavelength of 0.40 μm or more and 1.15 μm or less in the eyeball is high. Therefore, by outputting light having a central wavelength of 0.40 μm or more and 1.15 μm or less from the light source, the light can be sufficiently irradiated to the fundus of the eye E. The silicon-based light receiving element has high sensitivity to light having a center wavelength of 0.40 μm or more and 0.95 μm or less. Further, since the chromatic dispersion of light having a central wavelength of 0.95 μm or more and 1.15 μm or less due to water is small, when light in this range is irradiated to the eye E, a fundus OCT image having a good image quality can be obtained. Therefore, by outputting light having a central wavelength of 0.40 μm or more and 1.15 μm or less from the light source, a tomographic image of the fundus of the eye E can be appropriately captured.

The light (an example of the 2 nd beam) output from the fundus oculi light source 76 is adjusted to light having only a P-polarization component, and then is output from an optical fiber (not shown) via the interferometer 77. The light emitted from the optical fiber passes through the lens 22, the polarization beam splitter 24, and the dichroic mirror 30, and is incident on the two-dimensional scanner 32. The two-dimensional scanner 32 scans the fundus of the eye E in 2 directions of the x direction and the y direction using the incident light. The light emitted from the two-dimensional scanner 32 passes through the dichroic mirror 34, is reflected by the dichroic mirror 56, and enters the objective lens 54. The light incident on the objective lens 54 passes through the objective lens 54 and the dichroic mirror 44, is condensed near the fundus portion of the eye E, and is irradiated to the fundus of the eye E. In the ophthalmologic apparatus of the present embodiment, the power (power) of the objective lens 54 is set so as to irradiate the fundus of the eye E with the convergent light. The position of the exit end of the optical fiber that emits the light output from the fundus oculi light source 76 can be moved in the direction of the optical axis (in other words, the direction in which the optical path L4 extends) and moved in accordance with the refractive power of the eye E.

The light reflected by the fundus portion of the eye E travels the same path as the above-described path, and is introduced into the interferometer 77 (an example of the 2 nd interferometer) via an optical fiber (not shown). The interferometer 77 combines light reflected by the fundus portion of the eye E and reference light separately generated using light output from the fundus oculi light source 76, detects interference light obtained by the combination, and outputs an interference signal. In the ophthalmologic apparatus of the present embodiment, a tomographic image of the fundus of the eye E is acquired by processing the interference signal output from the interferometer 77.

As is clear from the above description, in the fundus scanning optical system, the optical path L4, the optical path L5, the optical path L9, the optical path L10, and the optical path L12 are paths through which light passes. Therefore, between the anterior ocular segment scanning optical system and the fundus scanning optical system, a part of the optical path L4 (specifically, the range between the dichroic mirror 30 and the two-dimensional scanner 32), and a part of the optical path L5 and the optical path L12 are overlapped paths (an example of an overlapping section), the optical path L8, the optical path L6, and the optical path L3 are paths through which only light of the anterior ocular segment scanning optical system passes (an example of a 1 st non-overlapping section), and the other part of the optical path L4, the optical path L9, and the optical path L10 are paths through which only light of the fundus scanning optical system passes (an example of a 2 nd non-overlapping section).

Next, the total refractive power measurement optical system will be explained. A light projection system that projects light to the eye E of the total refractive power measurement optical system has the same configuration as that of the light projection system of the fundus scanning optical system. Therefore, a light receiving system of the total refractive power measurement optical system will be described. As shown in fig. 4, the total refractive power measurement optical system is constituted by a dichroic mirror 44, an objective lens 54, a dichroic mirror 56, a dichroic mirror 34, a two-dimensional scanner 32, a dichroic mirror 30, a polarizing beam splitter 24, a lens 20, a reflecting mirror 18, an aperture 17, a lens 16, a ring lens 14, and a two-dimensional sensor 12.

As is clear from comparison of fig. 3 and 4, the path of light scattered at the fundus of the eye E is the same as that of the fundus scanning optical system from the dichroic mirror 44 to the polarization beam splitter 24. Only the S-polarized component of the light scattered in the fundus of the eye E to be examined is reflected by the polarization beam splitter 24, and it is irradiated toward the mirror 18 via the lens 20. The light irradiated to the mirror 18 passes through the aperture 17, the lens 16, and the ring lens 14, and forms an annular image on the detection surface of the two-dimensional sensor 12. The total refractive power of the eye E to be examined is calculated from the annular image imaged by the two-dimensional sensor 12. In the present embodiment, the light scattered in the fundus of the eye E is imaged in a ring shape on the light-receiving surface of the two-dimensional sensor 12 by using the ring lens 14, but the present invention is not limited to this example, and for example, a lens array may be used instead of the ring lens 14 to form a dot pattern on the light-receiving surface of the two-dimensional sensor 12. The diaphragm 17, the lens 16, the annular lens 14, and the two-dimensional sensor 12 are integrated, and are movable in the direction of the optical axis (optical path L1) and in accordance with the total refractive power of the eye E.

As shown in fig. 5, the front monitor optical system is composed of

LEDs

46, 48, a dichroic mirror 44, an objective lens 42, a total reflection mirror 40, a dichroic mirror 34, an aperture 70, a lens 72, and a two-dimensional sensor 74.

The

LEDs

46, 48 are disposed diagonally in front of the eye E and irradiate the anterior segment of the eye

E. The LEDs

46, 48 irradiate the eye E with light having a central wavelength of 0.76 μm. The light reflected by the eye E is reflected by the dichroic mirror 44, passes through the objective lens 42, is reflected by the total reflection mirror 40, passes through the dichroic mirror 34, the stop 70, and the lens 72, and forms a front image of the anterior ocular segment on the two-dimensional sensor 74. The anterior segment image of the eye E imaged by the two-dimensional sensor 74 is displayed on a display device not shown. Further, the diaphragm 70 is disposed at the back focus of the objective lens 42, and the image magnification does not change even if the anterior segment image is defocused.

As shown in fig. 6, the position detection light projection optical system is constituted by an LED68, a lens 66, a dichroic mirror 58, a dichroic mirror 56, an objective lens 54, and a dichroic mirror 44. The LED68 emits light with a center wavelength of 0.94 μm. The light emitted from the LED68 passes through the lens 66,

dichroic mirrors

58 and 56, objective lens 54, and dichroic mirror 44, and irradiates the cornea of the eye E. The light applied to the eye E is specularly reflected on the corneal surface of the eye E, and a virtual image of the light emitting surface of the LED68 is formed on the extension of the corneal vertex.

The position detection light receiving optical system detects the corneal vertex position in the direction (lateral direction) orthogonal to the optical axis (optical path L12), and detects the corneal vertex position in the optical axis direction (depth direction). The position detection light receiving optical system is composed of a lens 50, a two-dimensional sensor 52, a lens 38, and a two-dimensional sensor 36 (see fig. 7). The lens 50 and the two-dimensional sensor 52 are disposed diagonally in front of the eye E. The lens 38 and the two-dimensional sensor 36 are also arranged obliquely in front of the eye E. The lens 38 and the two-dimensional sensor 36, and the lens 50 and the two-dimensional sensor 52 are disposed at symmetrical positions with respect to the optical axis (optical path L12). The light reflected at a position slightly shifted from the corneal vertex of the eye E is obliquely reflected, passes through the lens 50, and a virtual image of the light emitting surface of the LED68 is projected on the two-dimensional sensor 52. Similarly, the light reflected at a position slightly shifted from the corneal vertex of the eye E passes through the lens 38, and a virtual image of the light emitting surface of the LED68 is projected on the two-dimensional sensor 36. In the ophthalmologic apparatus of the present embodiment, the corneal vertex position in the direction (lateral direction) orthogonal to the optical axis (optical path L12) is detected from the virtual image of the light emitting surface of the LED68 detected by the two-

dimensional sensors

36, 52, and the corneal vertex position in the optical axis direction (depth direction) is detected.

When the position of the corneal vertex of the eye E is detected based on the detection results of the two-dimensional sensor 36 and the two-dimensional sensor 52, the housing of the housing optical system 10 is driven by a driving device, not shown, to position the housing at the measurement position with respect to the corneal vertex of the eye E. Accordingly, the target portion 45 is positioned with respect to the eye E to be examined, and thereby the

objective lenses

42, 54 of the optical system 10 are positioned. When the target portion 45 (the

objective lenses

42, 54, etc. of the optical system 10) is positioned with respect to the eye E, the positions of the target portion 45, the

objective lenses

42, 54, etc. do not change with respect to the eye E during acquisition of the anterior segment tomographic image, fundus portion tomographic image, and total refractive power of the eye E.

As shown in fig. 8, the fixation target optical system is composed of an LED64, a lens 62, a reflecting mirror 60,

dichroic mirrors

58, 56, an objective lens 54, and a dichroic mirror 44. The LED64 emits white light. The light from the LED64 is transmitted through the image film printed with symbols for fixation of the subject, and reflected by the mirror 60. The light reflected by the reflecting mirror 60 is reflected by the dichroic mirror 58, and is transmitted through the dichroic mirror 56, the objective lens 54, and the dichroic mirror 44 to be irradiated to the eye E. In addition, the LED64 and the image film are movable in the optical axis direction (direction along the optical path L20), and the positions are adjusted in accordance with the total refractive power of the eye E.

As is clear from the above description, in the ophthalmologic apparatus of the present embodiment, no objective lens is disposed on the optical path L12 between the eye E and the dichroic mirror 44, the objective lens 42 dedicated to the anterior ocular segment scanning optical system is disposed on the optical path L8 dedicated to the anterior ocular segment scanning optical system, and the objective lens 54 dedicated to the fundus scanning optical system is disposed on the optical path L10 dedicated to the fundus scanning optical system. Therefore, compared to the related art, it is possible to suppress noise generated by reflected light reflected on the surfaces of the

objective lenses

42 and 54 from being mixed into the tomographic image.

That is, when a configuration is adopted in which a common objective lens is disposed on the optical path L12 between the eye E and the dichroic mirror 44 and a relay lens is disposed on an optical path dedicated to the fundus scanning optical system as in the conventional technique, 2 lenses, that is, the objective lens and the relay lens, are disposed in the fundus scanning optical system. That is, the lens power (refractive power) required for optically scanning the fundus oculi is divided by the 2 lenses of the objective lens and the relay lens. Therefore, the principal ray of light between the relay lens and the objective lens always approaches parallel to the optical axis regardless of the scanning angle, and enters the objective lens disposed on the eye side to be inspected at an angle approaching perpendicular. As a result, there is a problem that noise due to light reflected by the surface of the objective lens (i.e., the surface on the opposite side of the eye to be examined) is captured in the tomographic image for the fundus oculi (see fig. 9). However, in the fundus scanning optical system of the ophthalmic apparatus of the present embodiment, the dedicated objective lens 54 is disposed on the optical path L10, no lens is disposed between the objective lens 54 and the eye E to be examined, and no lens is disposed between the two-dimensional scanner 32 and the objective lens 54. Therefore, the lens power (refractive power) necessary for optically scanning the fundus oculi can be given by the objective lens 54. As a result, the incident angle of light incident on the objective lens 54 can be adjusted, and the light reflected by the objective lens 54 can be suppressed from mixing into the tomographic image. Similarly, in the anterior ocular segment scanning optical system of the ophthalmic apparatus of the present embodiment, the dedicated objective lens 42 is disposed on the optical path L8, no lens is disposed between the objective lens 42 and the eye E to be examined, and no lens is disposed between the two-dimensional scanner 32 and the objective lens 42. Therefore, the lens power (refractive power) necessary for optical scanning of the anterior segment can be imparted by the objective lens 42. As a result, the incident angle of light incident on the objective lens 42 can be adjusted, and thus, the light reflected by the objective lens 42 can be suppressed from being mixed into the tomographic image.

In addition, when a configuration is adopted in which a common objective lens is disposed on the optical path L12 between the eye E and the dichroic mirror 44 and a relay lens is disposed on an optical path dedicated to the fundus scanning optical system as in the conventional technique, 2 lenses, that is, the objective lens and the relay lens, are disposed in the light receiving system of the total refractive power measurement optical system. Therefore, the principal ray of the light between the relay lens and the objective lens is nearly parallel to the optical axis and enters the objective lens disposed on the eye side to be inspected at an angle close to perpendicular. As a result, an image generated by light reflected by the surface of the counter lens (the surface on the opposite side of the eye to be inspected) is mixed as noise in addition to an image reflected by the fundus portion of the eye to be inspected E. For example, as shown in fig. 10, the image of the inner circle (the image generated by the light reflected by the objective lens) is included in addition to the image of the circle located on the outermost periphery side (the image generated by the light reflected by the fundus portion). In the light receiving system of the total refractive power measurement optical system of the ophthalmic apparatus of the present embodiment, the objective lens 54 is disposed on the optical path L10, no lens is disposed between the objective lens 54 and the eye E, and no lens is disposed between the two-dimensional scanner 32 and the objective lens 54. Therefore, the light reflected by the surface of the objective lens 54 can be suppressed from mixing into the image captured by the refractive power measuring optical system.

In the ophthalmologic apparatus of the present embodiment,

dichroic mirrors

30, 34, 44, and 56 are used to branch and merge the optical path of the anterior ocular segment scanning optical system and the optical path of the fundus scanning optical system. Here, the dichroic mirror 30 (an example of a 3 rd dichroic mirror in the embodiment), the dichroic mirror 34 (an example of a 2 nd dichroic mirror in the embodiment), and the dichroic mirror 44 (an example of a 1 st dichroic mirror in the embodiment) disposed on the optical path of the anterior ocular segment scanning optical system are configured to reflect the light of the anterior ocular segment scanning optical system, respectively. This can suppress the occurrence of ghost noise of the iris of the eye E in the anterior segment tomographic image. That is, as shown in fig. 11, when the light 84 of the anterior ocular segment scanning optical system passes through the dichroic mirror DM, the light reflected by the exit surface 80 side of the dichroic mirror DM is further reflected (back surface reflection) by the entrance surface 82 side of the dichroic mirror DM, and the light 86 is irradiated to the eye E. The iris of the eye E has a large reflection intensity of light. Therefore, as shown in fig. 12, in addition to the anterior segment image based on the light 84, an image (ghost noise) generated due to the reflection of the light 86 by the iris is generated. In the ophthalmologic apparatus of the present embodiment, the dichroic mirrors 30, 34, and 44 disposed on the optical path of the anterior ocular segment scanning optical system are configured to reflect all the light of the anterior ocular segment scanning optical system, and therefore the occurrence of the ghost noise described above in the anterior ocular segment tomographic image can be suppressed.

Further, an AR coating may be applied to the light of the anterior ocular segment scanning optical system (for example, light having a center wavelength of 1.31 μm) on the back surface of the

dichroic mirrors

30, 34, 44. Accordingly, the reflection intensity of the light of the anterior ocular segment scanning optical system reflected by the back surfaces of the

dichroic mirrors

30, 34, and 44 can be reduced, and thus the generation of ghost noise in the anterior ocular segment tomographic image can be appropriately suppressed.

That is, even if the configuration is adopted in which the light of the anterior ocular segment scanning optical system is reflected by the dichroic mirror, as shown in fig. 13, most (for example, 98%) of the light 90 incident on the front surface 80 of the dichroic mirror DM becomes the reflected light 92, but a part (for example, 2%) thereof passes through the dichroic mirror DM and is reflected on the rear surface 82 of the dichroic mirror DM. The light 94 reflected by the back surface 82 of the dichroic mirror DM passes through the surface 80 of the dichroic mirror DM, and the light 96 passing through the surface is irradiated to the anterior segment of the eye E. Therefore, when the intensity of the light 94 reflected by the back surface 82 of the dichroic mirror DM is large, ghost noise due to the reflected light 94 is generated in the anterior ocular segment tomographic information. Therefore, by applying an AR coating (for example, 1% or less) to the back surface of the

dichroic mirrors

30, 34, 44 with respect to the light of the anterior ocular segment scanning optical system, it is possible to appropriately suppress the generation of ghost noise in the anterior ocular segment tomographic information.

For example, the anterior segment of the eye has various scattering characteristics of tissues compared with the fundus, and in order to image transparent tissues such as the cornea and the crystalline lens with sufficient contrast, as shown in fig. 14, the signal intensity of iris scattering is preferably at least 47dB or more in SN ratio, and more preferably 50dB or more in SN ratio when the image is taken once from the crystalline lens to the cornea. That is, the back surface of the cornea cannot be clearly recognized in an image in which the SN ratio of the signal intensity of iris scattering is 45dB, but the back surface of the cornea can be recognized in an image in which the SN ratio of the signal intensity of iris scattering is 47dB, and the back surface of the cornea can be clearly recognized in an image in which the SN ratio of the signal intensity of iris scattering is 50 dB. On the other hand, when the AR coating is not applied to the back surface of the dichroic mirror DM, the intensity of the reflected light 94 generated by the back surface reflection of the light transmitted through the dichroic mirror DM cannot be sufficiently reduced, and ghost noise of the iris is generated in the anterior segment tomographic image. For example, even if the surface reflectance of the dichroic mirror DM is set to 97% and the front-eye-section scanning light is preferentially reflected, when the AR coating is not applied to the rear surface of the dichroic mirror DM, the rear surface reflectance of the dichroic mirror DM is set to 4%. Therefore, the extinction ratio of the back reflected light of the dichroic mirror DM to the surface reflected light of the dichroic mirror DM is-44 dB, and ghost noise is generated. On the other hand, when the AR coating is applied to the rear surface of the dichroic mirror DM, the rear surface reflectance of the dichroic mirror DM is 2% or less. Therefore, the extinction ratio of the back reflected light of the dichroic mirror DM to the surface reflected light of the dichroic mirror DM is-47 dB or less, and ghost noise can be suppressed. In addition, when the light passes through the dichroic mirror DM (in the case shown in fig. 11), it is difficult to further suppress ghost noise. For example, even if the surface transmittance of the dichroic mirror DM is set to 97% and an AR coating is applied to the rear surface of the dichroic mirror DM (for example, the rear surface reflectance is 0.5%), the ghost signal extinction ratio due to the rear surface reflection of the dichroic mirror DM is only-38 dB, and ghost noise cannot be suppressed.

Therefore, by applying an AR coating (2% or less) to the back surface of the dichroic mirror DM with respect to the wavelength band of light of the anterior ocular segment scanning optical system, the extinction ratio of a ghost signal generated by the back surface reflection of the dichroic mirror DM can be made to be-47 dB or less. That is, the light energy of the light 96 reflected by the back surface 82 of the dichroic mirror DM is-47 dB or less with respect to the light energy of the light 92 reflected by the front surface 80 of the dichroic mirror DM. This can suppress ghost noise of the iris from being generated in the anterior segment tomographic image.

Here, an AR coating is applied to the back surface of the dichroic mirror DM for the wavelength of light that is generally transmitted. That is, when the optical system according to the present embodiment is configured, an AR coating is usually applied to the light of the fundus scanning optical system on the rear surface of the dichroic mirror DM. The reason for this is that, while the light component of the light of the wavelength on the reflection side (i.e., the light of the anterior ocular segment scanning optical system) that has passed through the mirror surface and reflected on the back surface is reflected on the back surface, and then most of the light component is reflected and largely attenuated when the light component passes through the mirror surface again, the light component is less attenuated when the light component passes through the mirror surface, and then the light component reflected on the back surface is reflected on the back surface, of the light of the wavelength on the transmission side (i.e., the light of the fundus oculi scanning optical system), the light component is hardly attenuated when the light component passes through the mirror surface, and thus the light component is likely to become noise.

The SN ratio of the iris signal intensity of the anterior segment tomographic image is 47dB or more, whereas the signal intensity of the retinal pigment epithelium is about 30dB in the fundus tomographic image. Therefore, even if the AR coating is not applied preferentially to the wavelength of the light transmitted through the back surface of the dichroic mirror DM (i.e., the light of the fundus scanning optical system), there is no problem that ghost noise of retinal pigment epithelium occurs in the fundus tomographic image.

In the above-described embodiment, the anterior ocular segment scanning optical system and fundus scanning optical system share the two-dimensional scanner 32, but the present invention is not limited to such an example. For example, a two-dimensional scanner dedicated to the anterior ocular segment scanning optical system may be disposed, and another two-dimensional scanner dedicated to the fundus scanning optical system may be disposed. In the above-described embodiment, the 1-piece objective lens (single lens) 42 is disposed in the anterior ocular segment scanning optical system, but the objective lens disposed in the anterior ocular segment scanning optical system may be configured by a combination of a plurality of lenses housed in the same barrel (for example, a combination of a convex lens and a concave lens or an aspherical lens). Similarly, the 1-piece objective lens 54 disposed in the fundus scanning optical system may be replaced with an objective lens formed by a combination of a plurality of lenses housed in the same barrel. In addition, when the objective lens portion is configured by a combination of a plurality of lenses, the lenses may be bonded so that the number of interfaces with air is minimized.

Specific examples of the techniques disclosed in the present specification have been described above in detail, but these are merely examples and do not limit the scope of the technical solutions. The technology described in the claims includes various modifications and changes to the specific examples described above. The technical elements described in the present specification or drawings can exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing.

Claims

1. An ophthalmic device, characterized in that,

having a 1 st light source, a 2 nd light source, a 1 st scanning optical system, a 2 nd scanning optical system, a 1 st interferometer and a 2 nd interferometer, wherein,

the 1 st light source outputs a 1 st light beam;

the 2 nd light source outputs a 2 nd light beam;

the 1 st scanning optical system performs scanning within a 1 st range of the eye to be inspected using the 1 st light beam output from the 1 st light source;

the 2 nd scanning optical system scans a 2 nd range of the eye to be examined, which is different from the 1 st range, using the 2 nd light beam output from the 2 nd light source;

the 1 st interferometer acquires the 1 st range of tomographic information from 1 st interference light, wherein the 1 st interference light refers to interference light obtained from reflected light of the 1 st beam from the eye to be examined;

the 2 nd interferometer acquires the 2 nd range tomographic information from 2 nd interference light, wherein the 2 nd interference light refers to interference light obtained from reflected light of the 2 nd beam from the eye to be examined,

the center wavelength of the 1 st light beam and the center wavelength of the 2 nd light beam are different,

the 1 st scanning optical system has a 1 st objective lens section for irradiating the 1 st beam to the 1 st area of the eye to be examined,

the 2 nd scanning optical system has a 2 nd objective lens section for irradiating the 2 nd beam to the 2 nd field of the eye to be examined,

the 1 st light beam does not transmit the 2 nd objective lens part and transmits the 1 st objective lens part,

the 2 nd light beam does not transmit through the 1 st objective lens part and transmits through the 2 nd objective lens part.

2. An ophthalmic device according to claim 1,

the 1 st optical path has an overlapping section overlapping with the 2 nd optical path and a 1 st non-overlapping section not overlapping with the 2 nd optical path, wherein the 1 st optical path refers to the optical path of the 1 st light beam, the 2 nd optical path refers to the optical path of the 2 nd light beam,

the 2 nd optical path has the overlapping section and a 2 nd non-overlapping section that does not overlap with the 1 st optical path,

the 1 st objective lens part is arranged in the 1 st non-overlapping section,

the 2 nd objective lens portion is disposed in the 2 nd non-overlapping section.

3. An ophthalmic device according to claim 2,

the 1 st scanning optical system has a 1 st scanner that performs scanning using the 1 st light beam output from the 1 st light source,

the 2 nd scanning optical system has a 2 nd scanner that performs scanning using the 2 nd light beam output from the 2 nd light source,

the 1 st scanner is configured in the 1 st non-overlapping region,

the 2 nd scanner is configured in the 2 nd non-overlapping section.

4. An ophthalmic device according to claim 2,

further having a scanner that performs scanning using the 1 st light beam output from the 1 st light source and performs scanning using the 2 nd light beam output from the 2 nd light source,

the scanner is disposed in the overlap section and shared by the 1 st scanning optical system and the 2 nd scanning optical system,

the 1 st objective lens part is arranged between the scanner and the eye to be examined,

the 2 nd objective lens portion is disposed between the scanner and the eye to be examined.

5. An ophthalmic device according to claim 4,

the 1 st range is the anterior segment of the subject's eye,

the 2 nd range is a fundus portion of the eye to be examined,

the ophthalmic apparatus further has a target portion facing the eye to be examined,

the overlap section has a 1 st overlap section including a section connecting the eye to be examined and the target portion,

the ophthalmologic apparatus further includes a 1 st dichroic mirror, the 1 st dichroic mirror being disposed at a 1 st position, the 1 st position being a position branching from the 1 st overlapping section to the 1 st non-overlapping section and the 2 nd non-overlapping section,

the 1 st dichroic mirror reflects the 1 st light beam and transmits the 2 nd light beam.

6. An ophthalmic device according to claim 5,

an AR coating is applied to the back surface of the 1 st dichroic mirror for the wavelength band of the 1 st beam.

7. An ophthalmic device according to claim 5 or 6,

the overlap section has a 2 nd overlap section, the 2 nd overlap section including a section connecting a 2 nd position and the scanner, wherein the 2 nd position refers to a position where the 1 st non-overlap section and the 2 nd non-overlap section join or branch,

the ophthalmic apparatus further has a 2 nd dichroic mirror, the 2 nd dichroic mirror being disposed at the 2 nd position,

the 2 nd dichroic mirror reflects the 1 st light beam and transmits the 2 nd light beam.

8. An ophthalmic device according to claim 7,

an AR coating is applied to the back of the 2 nd dichroic mirror for the wavelength band of the 1 st beam.

9. An ophthalmic device according to claim 7 or 8,

a 3 rd dichroic mirror is further disposed at a 3 rd position different from the 2 nd position among positions at both ends of the 2 nd overlapping section,

the 3 rd dichroic mirror reflects the 1 st light beam and transmits the 2 nd light beam.

10. An ophthalmic device according to claim 9,

an AR coating is applied to the back of the 3 rd dichroic mirror for the wavelength band of the 1 st beam.

11. An ophthalmic device, characterized in that,

the 1 st light source outputs a 1 st light beam;

the 2 nd light source outputs a 2 nd light beam;

the 1 st range is the anterior segment of the subject's eye,

the 2 nd range is a fundus portion of the eye to be examined,

the ophthalmologic apparatus further includes a 1 st dichroic mirror, the 1 st dichroic mirror being disposed at a 1 st position, wherein the 1 st position is a position branching from the 1 st overlapping section to the 1 st non-overlapping section and the 2 nd non-overlapping section,

the 1 st dichroic mirror reflects the 1 st light beam and transmits the 2 nd light beam,